U.S. Open Day 9 After Dark: Wozniacki beats hobbled Sevastova, Djokovic tops Tsonga

Caroline Wozniacki eased her way to the U.S. Open semifinals on Tuesday, beating a clearly hobbled AnastasijaSevastova 6-0, 6-1 at Arthur Ashe Stadium.

Sevastova rolled her ankle and fell to the ground on the first point of the second game. After Sevastova's injury, Wozniacki quickly took control of the match, cruising through the first set in 31 minutes and winning the second in 33 minutes.

In the night session finale, Novak Djokovic advanced after Jo-Wilfried Tsonga retired. Djokovic was leading 6-3, 6-2 at the start of the third set when Tsonga retired.

For a more in-depth look at Tuesday night's matches, see below.

To read about Tuesday's Day Session—namely Angelique Kerber and Gael Monfils advancing to the semifinals—check out SI.com's recap.

Results Roundup

Wozniacki d. Sevastova: You have to feel bad for Anastasija Sevastova. Playing in her first–ever Grand Slam quarterfinal, she rolled her ankle in the second game of the match—and her level of play significantly and immediately dropped.

Wozniacki took advantage, and came away with a 6-0, 6-2 victory.

"I think I was just extra focused, because I saw her fall in that second game. She stood up, and I knew if she can still walk and still put weight on it and stuff then she's going to go obviously more for her shots and stuff like that," Wozniacki said. "But I thought, cool. I kept serving well and made her run. I'm pleased with how I managed to keep composed."

Step back and look at the bigger picture: Unseeded, Caroline Wozniacki is in the U.S. Open semifinals for the fifth time. In her previous four appearances, she's made the final twice, never winning that elusive Slam title.

I doubt many people were predicting Wozniacki would be a semifinalist when she was down a set in her opening match against Taylor Townsend.

Sevastova, meanwhile, will obviously be disappointed to go out this way. She had a wonderful run in Flushing, including her upset of No. 3 Garbine Muguruza, and hopefully she can build on her success at this year's U.S. Open.

Wozniacki will face No. 2 seed Angelique Kerber in the semifinals. Do we have to wait two days to watch that match?

No. 1 Novak Djokovic d. No. 9 Jo-Wilfried Tsonga: Tsonga retired at the start of the third set, but in all likelihood it simply hastened his inevitable defeat. Djokovic was up 6-3, 6-2 when Tsonga bowed out of the match due to a knee issue.

Djokovic's path to the semifinals has been remarkable. After beating Jerzy Janowicz in his opening match, he won the next two matches in a walkover and a first-set retirement, respectively. Then he beat Kyle Edmund in straight sets before Tuesday's retirement.

Djokovic played well—though not quite to the level of his incredible fourth–round performance—but Tsonga blew a number of good opportunities. At one point, he double–faulted three times in one game, giving away a break. He hit 36 unforced errors and just 11 winners. After responding to a Djokovic break with a break of his own, getting the first set back on serve, he allowed Djokovic to break him again.

Djokovic, aiming for his third Grand Slam title this season, will face Gael Monfils in the semifinals.

Wozniacki contemplating retirement?

One interesting bit from Caroline Wozniacki's post–match press conference: She declined to refute a Danish media report in which her father reportedly said she's contemplating retirement.

"I think I don't want to really talk about that now. When I feel ready to open up and say something then I will, but for now I'm just here to play this tournament," she said. "Hopefully I have two more matches here. Yeah, it's really all I'm focused on right now."

What does it mean? Who knows, really. She didn't deny the report—but she also didn't confirm it. Something to keep an eye on. Wozniacki, by the way, is only 26.

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